Coastwide
An oil field where the California Coastal Commission will decide to return it to the Los Cerritos wetlands restored to a prettier, healthier wetlands area in Long Beach December 7, 2018. Photo by Thomas R. Cordova

Nature can soften impacts of rising seas—if we let it

This story is part of a Long Beach Post multi-part series, “Close to Home: How climate change is shaping the future of Long Beach.” For the full series, click here.

By the end of the century, rising seas will force Long Beach to find ways to protect homes and businesses—or see some of them swallowed by the sea.

While seawalls, breakwaters and other barriers are already deployed up and down portions East Coast and West Coast, not all solutions are made of concrete and stone.

Some say the future of protecting California’s coasts, and the developments behind them, will include more natural solutions like restoring wetlands and other habitats so they can help slow storm surges and combat other effects of sea level rise.

“Habitats or ecosystems serve many many benefits, including physical protections in many cases,” said Evyan Sloane, a project manager for the State Coastal Conservancy.

“When you’re building a wetland or a dune or a beach on the coast you can provide a habitat for different species including endangered species, you can sometimes sequester (carbon dioxide), further fighting against what’s causing climate change, and you can sometimes protect against erosion.”

Sloane worked on a project in Seal Beach in which sediment was dredged and then transported to two sites where it was layered on top of existing salt marshes. The project was located within the Seal Beach National Wildlife Refuge just south of the Long Beach border.

It raised the level of the salt marsh by about 8.5 inches above grade, something that researchers said could not only improve the ecosystem, but also make it more resilient to rising seas.

The project was part of a series of case studies performed by Coastal Resiliency, a group that advocates for natural modifications to coastal areas and includes researchers from a number of organizations including the Nature Conservancy, the National Oceanic and Atmospheric Administration and the California Resources Agency.

Some of these solutions included building a living shoreline in the San Francisco Bay to reduce wave energy through the creation of oyster reefs and eelgrass beds. The project resulted in a 30 percent reduction in wave energy.

One project involved a form of managed retreat in which the coastal city of Ventura restored dunes in front of a parking lot that was being damaged by wave activity. The parking lot was also moved back, resulting in the beach being widened by about 60 feet.

Sloane is hopeful that these types of projects will be recognized more often in the future for their win-win potential.

“We could have a coastline that’s all seawalls and ocean and no habitat and no recreation and all the other benefits, or we can have wetlands that you can kayak in and see birds and go to the beach and lay your towel down on the sand,” Sloane said.

Read full article . . .